Abstract

The purpose of the present study is to
determine the effects of state-level assault weapons bans and
concealed weapons laws on state-level murder rates. Using data
for the period 1980 to 2009 and controlling for state and year
fixed effects, the results of the present study suggest that states
with restrictions on the carrying of concealed weapons had
higher gun-related murder rates than other states. It
was also found that assault weapons bans did not significantly
affect murder rates at the state level. These results suggest
that restrictive concealed weapons laws may cause an
increase in gun-related murders at the state level. The
results of this study are consistent with some prior research
in this area, most notably Lott and Mustard (1997).

Video by Norway's Kongsberg of a flight test of its Naval Strike
Missile (NSM), basis of the Joint Strike Missile under development
for the F-35 JSF. Here, the fire-and-forget missile is launched from
land at the Pt Mugu, Calif., test range and is filmed by a chase
aircraft as it sea-slims a few feet above the Pacific, flying over an
island to acquire and attack a target ship on the otther side.
Kongsberg says this mission profile gave the NSM's imaging-infrared
seeker just 1.5 seconds to acquire and identify the ship as its
pre-programmed target.

A sieve in general is intended to find the numbers which are remainders when a set of numbers are divided by a second set. Generally, they are used in finding solutions of diophantine equations or to factor numbers. A Lehmer sieve will signal that such solutions are found in a variety of ways depending on the particular construction.

The first Lehmer sieve in 1926 was made using bicycle chains of varying length, with rods at appropriate points
in the chains. As the chains turned, the rods would close
electrical switches, and when all the switches were closed
simultaneously, creating a complete electrical circuit, a solution
had been found. Lehmer sieves were very fast, in one particular
case factoring

in 3 seconds.

In the 1930s or thereabouts he was reluctantly going to a fellow
professor's house for a cocktail party, to celebrate the return from
China of the man's wife. She greeted him at the door and said "You
mathematicians count things, right? Tell me something about this!" and
handed him one of those insanely complicated wooden Chinese puzzles you
take apart but probably will never get back together again.

He said, twirling the thing around in his hands, "Well, if you count the
number of corners, and subtract all the edges, and then add the faces,
you get...let's see now...you get 2!"

"Nobody can count that fast!" she said. "I assure you it is true,
madam" he replied. She went off in a corner with some tape and a
pencil. Fifteen minutes later she said, in an astonished voice, "It's
true!"